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/* See LICENSE file for copyright and license details. */
#include "arg.h"
#include "stream.h"
#include "util.h"
#include <ctype.h>
#include <unistd.h>
static void
usage(void)
{
eprintf("usage: %s\n", argv0);
}
int
main(int argc, char *argv[])
{
char buf[2 + 3 * sizeof(size_t) + sizeof(((struct stream *)0)->pixfmt)];
char magic[] = {'\0', 'u', 'i', 'v', 'f'};
char b;
char *p;
size_t i, ptr;
ssize_t r;
ARGBEGIN {
default:
usage();
} ARGEND;
if (!argc)
usage();
for (ptr = 0; ptr < sizeof(buf);) {
r = read(STDIN_FILENO, buf + ptr, 1);
if (r < 0)
eprintf("read <stdin>:");
if (r == 0)
goto bad_format;
if (buf[ptr++] == '\n')
break;
}
if (ptr == sizeof(buf))
goto bad_format;
p = buf;
for (i = 0; i < 5; i++) {
r = read(STDIN_FILENO, &b, 1);
if (r < 0)
eprintf("read <stdin>:");
if (!r || b != magic[i])
goto bad_format;
}
for (i = 0; i < 2; i++) {
if (!isdigit(*p))
goto bad_format;
while (isdigit(*p)) p++;
if (*p++ != ' ')
goto bad_format;
}
while (isalnum(*p) || *p == ' ') {
if (p[0] == ' ' && p[-1] == ' ')
goto bad_format;
p++;
}
if (p[-1] == ' ' || p[0] != '\n')
goto bad_format;
for (i = 0; i < ptr; i += (size_t)r) {
r = write(STDOUT_FILENO, buf + i, ptr - i);
if (r < 0)
eprintf("write <stdout>:");
}
return 0;
bad_format:
eprintf("<stdin>: file format not supported\n");
}
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